I think there is enough defense in this deck without the second bone/storm combo. I've finished a lot of games against tougher gods with 2 firestorms, and 2 bonewalls sitting in my hand. The gods which are particularly susceptible to bone/storm are easy to beat anyways.
As far as Seism, i've had phenominal success against him lately. Every kind of defense this deck packs is good against him if you can play it, and the novas get you around quicksand. I find that you can best abuse his rewinds by playing a FFQ, a Druid, and a Oty all together when you're getting low on cards. He'll rewind all of them, but it's far better than him rewinding the same card several times and using up all your quanta of that type. If instead you get both your quints sooner in the match, use the second on the FFQ rather than the druid, he'll rewind fireflies, which are cheap, and you aren't using air quanta for anything after your queenie is out.
When i was running PA, i thought i needed it. Now that i don't, i don't miss it at all. Only Divine Glory and Rainbow have both healing and perm control, and PA isn't going to change your win % against these two anyways, since your success has as much to do with what they draw as what you do.
WL